ABSTRACT The prevalence of obesity consistently increases from preschool (PS) (9.4%) to school-age (19.6%) to adolescents (20.6%) to adulthood (36.5%) with 50% of obese PS children becoming obese as adults. Since obesity early in life predicts obesity in later life, there is a critical need to help families with young children self- regulate healthy lifestyle behaviors. This proposal focuses on self-regulating lifestyle behaviors (eating, physical activity, and sleep) through a goal-setting intervention based on an event history calendar (EHC) retrieval of lifestyle patterns for low-income parent-preschool dyads. An event history calendar (EHC) is a reflective tool used to present a visual history of lifestyle behavior patterns in the context of significant life events from the families' real world to facilitate realistic goal-setting. We propose that EHCs can be used as a self-regulation strategy to facilitate realistic goal-setting leading to decreased risk of obesity and potential comorbidities. The overall goal of this proposed study is to demonstrate the feasibility of using event history calendars (EHC) as an innovative self-regulation strategy to facilitate goal-setting and improve health and lifestyle behavior outcomes related to weight with low-income parent-PS child dyads. Using a self regulation model, this study presents a novel approach to improve lifestyle behaviors in low- income families by (1) exploring the efficacy of EHCs as an innovative self-regulation goal-setting prevention tool, 2) strengthening three lifestyle behaviors: eating, physical activity, and sleep; and 3) using a dyadic approach with low-income parents and PS children to tailor goals over time. Our randomized control trial (RCT) utilizes EHCs with a tapered strategy over 6 months with parent-PS child (?3?<6 years) dyads stratified into groups by child age, 3-, 4-, and 5-years-old and sex. A 3-group RCT approach will be used to determine the most effective self-regulation goal-setting strategy (Parent only EHC; Parent + PS child EHC; No EHC/usual care) to change parent-reported and objective outcomes in low-income families over time. The specific aims include: Aim 1: Determine the feasibility of a self-regulation strategy using a goal setting intervention based on EHC retrieval of lifestyle patterns by PS child-parent dyads from baseline to six months. The aspects of feasibility being targeted will include a) recruitment, b) retention, c) adherence to the intervention sessions, d) assessment, e) meeting self-identified goals, and f) revising goals. Aim 2: Explore the preliminary effect of the EHC as a self-regulation goal-setting intervention (Parent only EHC; Parent + PS child EHC; No EHC/usual care) on a) parent-report outcomes [Lifestyle behaviors (Family, Nutrition, Physical Activity tool (FNPA); Child routine inventory (CHI)] and b) objective outcomes [BMI, waist circumference (WC), physical activity and sleep duration via accelerometry].